I have the logitech k800 keyboard but can't seem to get certain shortcuts working. I change in the keyboard shortcut settings volume up and down and it actually takes the key assignment but does not take effect when trying to use. After trying for a while I also tried to create a custom shortcut after with the command amixer -q sset Master 10%- Finally I tried changing the command to touch a file to see if it is actually responding but nothing. How can it take the key as an assignment in the shortcut settings but not to actually respond when pressing it. FYI other keys work like mute, next track etc. There is just 3 keys shortcuts not currently working.

Thanks